FACTORS ASSOCIATED WITH INFECTED OBSTRUCTION AND PROLONGED HOSPITALIZATION IN PATIENTS WITH UROLITHIASIS

Introduction. Urolithiasis may be complicated by infected obstruction requiring timely treatment. Factors associated with this complication and prolonged hospitalization remain insufficiently studied. Aim. To identify clinical, laboratory, and radiological factors associated with infected upper urinary tract obstruction and prolonged hospitalization in patients with urolithiasis. Materials and methods. A single-center retrospective observational study was conducted among patients with urolithiasis admitted to the Department of Urology of the Central City Clinical Hospital in Almaty in 2025. The analysis was based on data obtained from medical records and the hospital medical information system. A total of 471 hospital admissions were included. The primary outcomes were infected obstruction and prolonged hospitalization, defined as a hospital stay exceeding 4 bed-days. Binary logistic regression was used to assess the associations. Results. The median age of the patients was 46 years (36–61), and men accounted for 57.7% of the study population. The most common diagnosis was a ureteral stone, accounting for 66.9% of cases. Infected obstruction was identified in 40 patients (8.5%), while prolonged hospitalization was recorded in 225 patients (47.8%). Patients with infected obstruction had larger stones, a higher frequency of body temperature ≥38 °C and pyuria, and higher blood leukocyte counts. In the multivariable model, the independent factors associated with infected obstruction were body temperature ≥38 °C (OR 16.26; 95% CI 7.35–35.98; p<0.001), blood leukocyte count (OR 1.15 per 1×10⁹/L increase; 95% CI 1.07–1.24; p<0.001), and stone size (OR 1.09 per 1-mm increase; 95% CI 1.00–1.18; p=0.040). Male sex was the only statistically significant factor associated with prolonged hospitalization (OR 1.48; 95% CI 1.01–2.18; p=0.045). Conclusion. Among hospitalized patients with urolithiasis, infected obstruction has a distinct clinical and laboratory profile and is associated with fever, leukocytosis, and larger stone size. These indicators may be used for the early identification of patients at risk of a potentially complicated clinical course and for determining the need for timely urological assessment.